Radiation therapy is a therapeutic method using radiation rays, such as α, β, or γ rays generated by radioactive isotopes, or using X-rays, electron rays, proton rays or other particles generated by various X-ray radiotherapy apparatuses, to impinge diseased tissues of a body. In modern medical therapeutic methods, radiation therapy is widely used in fields such as tumor therapy, etc.
For example, a medical linear accelerator system is a commonly used particle accelerating apparatus for radiation therapy. A medical linear accelerator includes a treatment head in which a radiation source is arranged for irradiating a diseased tissue.
Besides a series of components such as an accelerating tube, an electron gun, movable targets, a magnet-deflection system, a collimator, a flattening filter, etc., the treatment head further includes a high-density shielding layer made of lead for preventing extra radiation rays emitted from the radiation source from irradiating a body during an operation of the linear accelerator, and thus the treatment head has a large mass. The linear accelerator is also provided with counterbalance weights to offset the overturning torque of the treatment head, and thus the volume of an existing linear accelerator is large, which results in troubles for installation, transport, calibration, and maintenance thereof
Additionally, during a radiation therapy, besides the linear accelerator generating radiation rays, an imaging apparatus, such as a computed tomography (CT) scanner, is also needed to cooperate with the linear accelerator to position the diseased tissue of a body.
Accordingly, during a radiation therapy, the diseased tissue of a patient needs to be positioned via the CT, and then the patient is moved to the linear accelerator to receive the radiation therapy to the diseased tissue, since both the linear accelerator and the CT scanner have large volumes, the distance the patient needs to be moved is large, and the course of the movement is complicated, which easily results in errors in positioning.
Therefore, the problems need to be solved by one person skilled in the art are how to reduce the complexity of a treatment course, to improve the efficacy of a radiation therapy, and to reduce positioning errors during positioning a diseased tissue and irradiating the diseased tissue.